Hydrated lime is used in many asphalt mixes and is generally required by many states to improve properties of pavements made from hot mix asphalt. Hydrated lime can be also used as an anti-stripping agent. The asphalt industry has used different approaches to introduce hydrated lime to asphalt mix. For example, the following methods have been used: dry hydrated lime injected into drum mixer, dry hydrated lime added to aggregate in pug mill, dry hydrated lime added to moist aggregate with marination, and hydrated lime slurry added to aggregate with or without marination. See, National Lime Association, How to Add Hydrated Lime to Asphalt, An Overview of Current Methods (September 2003), page 2.
Hot mix asphalts (HMA) are a mix of aggregate heated to about 300° F. to 350° F. with a similarly heated asphalt based binder, which generally includes asphalt and or asphalt and polymer.
A lower temperature alternative to HMA is warm mix asphalt (WMA). However, WMA tend to be costly due to the use of additives including waxes, amines and surfactants.
The present disclosure has been developed as an approach to introduce hydrated lime into a warm mix asphalt, while minimizing costs to recycle lost hydrated lime particles and reduce costs to dry aggregate particles.